Geoscience Reference
In-Depth Information
Figure 6.5 Unconformity at Siccar Point, Scotland, one of the unconformities recognised by James Hutton. Here vertical beds
of Silurian age (a) are overlain by gently aligned, nearly horizontal beds of Devonian Old Red Sandstone (d) (from Lyell,
Manual of Elementary Geology (1855), frontispiece).
